The water flywheel is comprised of two paddles encased in an enclosed tank of water. As you pull the cable, the paddles move through the water creating resistance. The beauty of this machine is it uses the mass/density of water. The paddles create the drag, so the harder you pull, the more resistance increases. Think about moving your hands through water. The faster you go, the more dense water feels. The slower you go, the less you feel the resistance. And this type of resistance is excellent for your joints. Click here to read the full review.

Flywheel sits in enclosed water tank to provide smooth, quiet, self-regulated resistanceSeries 4 performance monitor tracks workou...t intensity, stroke rate, heart rate, and moreHandcrafted rowing machine with "water flywheel" that replicates actual rowing feelStores upright; measures 83 x 22 x 21 inches (L x W x H) and weighs 108 poundsNo impact and Non-Load Bearing, perfect for users with Joint concerns read more
As I mentioned, the rowing experience with the WaterRower is amazing. I bought the rower for myself, but my wife was curious and decided to try it out. She loves it, and now rows almost daily. We have a treadmill that neither of us has used since we started rowing - the WaterRower is a much better workout and much more enjoyable at the same time. It's easy to adjust the intensity, pace and duration of your exercise. There is nothing to change on the rower (* see note below), you just row harder or faster, adjust how far you lean forward and back during your stroke. The WaterRower will keep up with you as your fitness increases, all you need to do is keep throwing more and more at it.
The recovery phase follows the drive. The recovery starts with the extraction and involves coordinating the body movements with the goal to move the oar back to the catch position. In extraction, the rower pushes down on the oar handle to quickly lift the blade from the water and rapidly rotates the oar so that the blade is parallel to the water. This process is sometimes referred to as feathering the blade. Simultaneously, the rower pushes the oar handle away from the chest. The blade emerges from the water square and feathers immediately once clear of the water. After feathering and extending the arms, the rower pivots the body forward. Once the hands are past the knees, the rower compresses the legs which moves the seat towards the stern of the boat. The leg compression occurs relatively slowly compared to the rest of the stroke, which affords the rower a moment to recover, and allows the boat to glide through the water. The gliding of the boat through the water during recovery is often called run.
This affordable rowing machine is streamlined, simple to use, built well, has a comfy seat with a realistic rowing movement, and especially good for a newbie. Because the cost of this machine is less than $150, it is popular on the net. As it has a hydraulic rower, resistance is provided by just one piston under the main key column. Along with a comfy cushioned seat, LCD screen, this machine provides 12 hydraulic cylinder resistances.